Paper straw

ABSTRACT

A paper straw 10 is comprised of an elongated paper tube 30 and a bending structure 20 composed in the tube 30. The bending structure 20 is comprised of a plural stiff part 21 and a plural soft part 22 alternately turn around thereof and make a tubular form. The paper tube is made from paper or the material made from plant. The stiff part 21 may have a large thickness and the soft part 22 may have a smaller thickness.

CROSS-REFERENCE TO RELATED APPLICATIONS

The corresponding Japanese application; priority to a foreign application is claimed.

-   -   Japanese patent application No. 2018-224302, filing date Nov.         29, 2018.     -   Japanese design application No. 2018-026309, filing date Dec. 3,         2018.

TECHNICAL FIELD

This invention relates generally to a paper straw for drinking liquids.

BACKGROUND ART

There are various types of plastic straws.

However, because of environmental problems, plastic straws are prohibited or restricted to use. So, paper straws are introduced and increasing world widely.

CITATION LIST Patent Literature

[PTL 1] JP(Open)2009-160251

SUMMARY OF INVENTION Technical Problem

But there is a problem that the paper straw is difficult to be bent. In case of the plastic straw, plastic material become soft and a bellow shape is easily formed when heated. On the contrary paper material does not become soft even when heated. Therefore, the bellow shape is difficult to be formed.

Without the bellow shape, the paper straw is easily collapsed when bent and the liquid is not able to flow inside thereof (FIG. 4).

Solution to Problem

A paper straw comprising an elongated paper tube and a bending structure composed in the tube, wherein said bending structure is comprised of stiff parts and soft parts alternately turn around thereof and form the tube.

A paper straw comprising an elongated paper tube and a bending structure composed in the tube, wherein said bending structure is comprised of spiral stiff parts and spiral soft parts alternately turn around thereof and form the tube.

Above mentioned paper straw, wherein the thickness of the stiff part is larger than the thickness of the soft part.

Above mentioned paper straw, wherein the stiffness of the material of the stiff part is bigger than the stiffness of the material of the soft part.

Advantageous Effects of Invention

Based on above mentioned invention, it becomes possible to bend the paper straw smoothly, solving the above-mentioned problems.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a front view and a right side view of the first embodiment of this invention.

FIG. 2 is a front view of the bending structure of the first embodiment of the invention.

FIG. 3 is s longitudinal section of FIG. 2.

FIG. 4 is a front view of the bending structure of the first embodiment and the previous art, when bend.

FIG. 5 is a front view of the bending structure of the second embodiment of the invention.

FIG. 6 is an upper view of the manufacturing machine of the paper straw.

FIG. 7 is an upper view of the grinder.

FIG. 8 is a longitudinal section of the bending structure of the third and the fourth embodiments of the invention.

FIG. 9 is a front view of the bending structure of the fifth embodiment of the invention.

FIG. 10 is a front view and a right side view of the fifth embodiment of the invention.

FIG. 11 is a front view of the fifth embodiment of the invention when bent.

DESCRIPTION OF EMBODIMENTS

Referring to FIG. 1, FIG. 2, FIG. 3, and FIG. 4, the first embodiment of the invention is shown. A paper straw 10 is comprised of an elongated paper tube 30 and a bending structure 20 composed in the tube 30. The bending structure 20 is comprised of a plural stiff part 21 and a plural soft part 22, alternately turn around thereof and make a tubular form.

The paper straw is made from paper or the organic material such as plant. The stiff part 21 has a large thickness and the soft part 22 has a smaller thickness. The soft part 22 is made by grinding or pressing the surface of the bending structure 20.

FIG. 4 shows the way of bending the paper straw. A previous paper straw collapses when bent and a hollow therein becomes small. On the contrary, in case of the paper straw 10 of this embodiment, even though the soft part 22 is deformed, the stiff part 21 keeps the round shape. Therefore, the round hollow therein maintains the enough space to drink fluid.

Referring to FIG. 5, the second embodiment of the invention is shown. Hardening means such as adhesive is added on the surface of the bending structure 20 to create hardening part 21A. Electromagnetic or electronic radiation may be used as the hardening means.

Referring to FIG. 8, the third embodiment A and the fourth embodiment B of the invention are shown. The tube 30 of the third embodiment is comprised of a base layer 31 and an inner layer 32. The base layer 31 is stiffer than the inner layer 32.

An outer layer 33 is added on the base layer 31, in case of the fourth embodiment.

Referring to FIG. 6 and FIG. 7, the manufacturing method is shown. A plurality of paper tapes 92 are supplied from tape reels 91 and the adhesives are applied on the tapes 92. The paper tapes 92 are wound around a rotating shaft 93 and move to the right direction. A plural grinder 95 also move along the paper tapes 92 and grind the surface of the paper tapes 92.

Referring to FIG. 9, FIG. 10 and FIG. 11, the fifth embodiment of the invention is shown. As mentioned above, a plural tape 92 are wound spirally when manufacturing the paper straw 10. The spiral stiff part 21 is made thick and the spiral soft part 22 is made thin. Then, the spiral stiff part 21 helps the paper straw 10 to bend keeping the round tubular shape, although the spiral soft part 22 deforms. A single tape 92 or a plural tape 92 may be used for making the spiral stiff part 21.

The stiff material may be used for the stiff part 21 and the soft material may be used for the soft part 22.

By this embodiment, the paper straw 10 can be manufactured using the conventional machine by choosing the materials and adjusting the machine. Besides, the additional process such as making the bellow is not necessary.

INDUSTRIAL APPLICABILITY

This invention is applicable not only to a home use but also a business use such as cafés or restaurants.

REFERENCE SIGNS LIST

-   10 is a straw. -   20 is a bending structure. -   21 is a stiff part. -   21A is a hardening part. -   22 is a soft part. -   22A is a non-hardening part -   30 is a tube. -   31 is a base layer. -   32 is an inner layer. -   33 is an outer layer. -   90 is a straw manufacturing machine. -   91 is a tape reel. -   92 is a tape. -   93 is a shaft. -   94 a cutter. -   95 a grinder. -   96 a suction tool. 

1. A paper straw comprising; an elongated paper tube; and a bending structure composed in the tube; wherein said bending structure is comprised of stiff parts and soft parts alternately turn around thereof and form the tube.
 2. A paper straw comprising; an elongated paper tube; and a bending structure composed in the tube; wherein said bending structure is comprised of spiral stiff parts and spiral soft parts alternately turn around thereof and form the tube.
 3. The paper straw of claim 1; wherein the thickness of the stiff part is larger than the thickness of the soft part.
 4. The paper straw of claim 1; wherein the stiffness of the material of the stiff part is bigger than the stiffness of the material of the soft part.
 5. The paper straw of claim 2; wherein the thickness of the stiff part is larger than the thickness of the soft part.
 6. The paper straw of claim 2; wherein the stiffness of the material of the stiff part is bigger than the stiffness of the material of the soft part. 